TWI685723B - Method for parameter determination and apparatus thereof - Google Patents

Abstract

A method and apparatus to measure overlay from images of metrology targets, images obtained using acoustic waves, for example images obtained using an acoustic microscope. The images of two targets are obtained, one image using acoustic waves and one image using optical waves, the edges of the images are determined and overlay between the two targets is obtained as the difference between the edges of the two images.

Description

Parameter determination method and device

The present invention relates to a method and apparatus that can be used for detection (e.g., metrology) of device manufacturing by, for example, lithography technology, and to a method of manufacturing a device using lithography technology.

The lithography device is a machine constructed to apply the desired pattern to the substrate. Lithography devices can be used, for example, in the manufacture of integrated circuits (ICs). A lithography apparatus can, for example, project a pattern (also often referred to as a "design layout" or "design") at a patterned device (such as a photomask) onto a radiation-sensitive material (resist) provided on a substrate (such as a wafer) Agent) layer.

In order to project the pattern on the substrate, the lithography device may use electromagnetic radiation. The wavelength of this radiation determines the minimum size of features that can be formed on the substrate. Typical wavelengths currently in use are 365 nm (i-line), 248 nm, 193 nm, and 13.5 nm. Compared to a lithography apparatus using radiation having a wavelength of 193 nm, for example, using extreme ultraviolet (EUV) radiation having a wavelength in the range of 4 nm to 20 nm (eg, 6.7 nm or 13.5 nm) The lithography device can be used to form smaller features on the substrate.

Low-k ₁ lithography can be used to handle features with dimensions smaller than the classic resolution limit of lithography devices. In this process, the resolution formula can be expressed as CD=k ₁ ×λ/NA, where λ is the wavelength of the radiation used, NA is the numerical aperture of the projection optics in the lithography device, and CD is the “critical size” (Usually the smallest feature size printed, but in this case half pitch) and k ₁ is the empirical resolution factor. In general, the smaller k _{1 is} , the more difficult it is to reproduce patterns and shapes similar to those planned by circuit designers on the substrate to achieve specific electrical functionality and performance. To overcome these difficulties, complex fine-tuning steps can be applied to the lithography projection device and/or design layout. These steps include, for example, but not limited to: optimization of NA, custom lighting schemes, use of phase-shift patterned devices, various optimizations of design layout, such as optical proximity correction (OPC, sometimes in design layout) It is called "optical and process calibration"), or other methods usually defined as "resolution enhancement technology" (RET). Alternatively, the stability of the control loop for the strict control of the lithography apparatus used to improve the reproduction of _a pattern at the low k.

Therefore, in the patterning process, it is necessary to frequently measure the generated structure, for example, for process control and verification. Various tools for making such measurements are known, including scanning electron microscopes that are often used to measure critical dimensions (CD), and to measure stacking pairs (the accuracy of the alignment of two layers in a device) Special tools for measuring). The stack pair can be described in terms of the degree of misalignment between the two layers. For example, a reference to a measured stack pair of 1 nanometer describes the misalignment of the two layers by 1 nanometer.

Various forms of detection devices (such as weighing and measuring devices) have been developed for use in the lithography field. These devices direct the radiation beam onto the target and measure one or more properties of the redirected (e.g. scattered) radiation-for example, the intensity at a single angle of reflection that varies according to wavelength; the one that varies according to the angle of reflection Or the intensity at multiple wavelengths; or the polarization that changes according to the angle of reflection-to obtain the "spectrum" of the attribute of interest that can be used to determine the target. The determination of the attribute of interest can be performed by various techniques: for example, target reconstruction by repeated paths such as tightly coupled wave analysis or finite element method; library search; and principal component analysis.

The invention discloses a method and a device for measuring a pair of self-weighting target images. The images are images obtained by using sound waves, for example, images obtained by using an acoustic microscope. A weighing and measuring device comprising a source for generating sound waves. A method includes using sound waves to measure a parameter of a patterning process, which further includes using sound waves to obtain a first image of a first target, using light waves to obtain a second image of a second target, and determining the first A characteristic of the image and the second image, and a parameter of the patterning process is determined as a difference between the characteristic of the first image and the characteristic of the second image. This feature is the edge of the image.

301‧‧‧ Acoustic Microscope

301A‧‧‧Bottom grating

301AA‧‧‧edge

301B‧‧‧Video

302‧‧‧Optical microscope

302A‧‧‧Top grating

302AA‧‧‧edge

302B‧‧‧Video

310‧‧‧Distance

401‧‧‧ Acoustic radiation

402‧‧‧Light radiation

B‧‧‧radiation beam

BD‧‧‧beam delivery system

BK‧‧‧Baking board

C‧‧‧Target part

CH‧‧‧cooling plate

CL‧‧‧computer system

DE‧‧‧Developer

IF‧‧‧Position sensor

I/O1‧‧‧input/output port

I/O2‧‧‧input/output port

IL‧‧‧Lighting system/illuminator

LA‧‧‧lithography device

LACU‧‧‧ Lithography Control Unit

LB‧‧‧Loading box

LC‧‧‧Lithography Manufacturing Unit

M ₁ ‧‧‧ Mask alignment mark

M ₂ ‧‧‧ Mask alignment mark

MA‧‧‧patterned device/mask

MT‧‧‧Measuring and weighing tool/spectral scatterometer

P ₁ ‧‧‧ substrate alignment mark

P ₂ ‧‧‧ substrate alignment mark

PM‧‧‧First locator

PS‧‧‧Projection system

PW‧‧‧Second positioner

RO‧‧‧ substrate handler or robot

SC‧‧‧spin coater

SC1‧‧‧First scale

SC2‧‧‧second scale

SC3‧‧‧third scale

SCS‧‧‧Supervision and Control System

SO‧‧‧radiation source

T‧‧‧support structure/mask table

TCU‧‧‧Coating and developing system control unit

W‧‧‧Substrate

WT‧‧‧Substrate table

Embodiments of the present invention will now be described by way of example only with reference to the accompanying schematic drawings, in which: Figure 1 depicts a schematic overview of a lithography device; Figure 2 depicts a schematic overview of a lithography manufacturing unit Figure 3 depicts a schematic representation of the overall lithography, which represents the cooperation between the three key technologies used to optimize semiconductor manufacturing; Figure 4 depicts in Figure 4A for use in accordance with the present invention includes an acoustic metrology device and optical metrology An example of a device, and the image of the measured stack-to-target is depicted in FIG. 4B.

Figure 5 depicts another embodiment of a combined acoustic and optical metrology device according to the present invention.

In this document, the terms "radiation" and "beam" are used to cover all types of electromagnetic radiation, including ultraviolet radiation (eg, with 365 nm, 248 nm, 193 nm Rice, 157 nanometers, or 126 nanometers) and extreme ultraviolet radiation (EUV, for example, having a wavelength in the range of about 5 nanometers to 100 nanometers).

The terms "reduced reticle", "reticle" or "patterned device" as used herein can be broadly interpreted as referring to a general patterned device that can be used to impart a patterned cross-section to the incident radiation beam , The patterned cross-section corresponds to the pattern to be generated in the target portion of the substrate; the term "light valve" can also be used in the context of this content. In addition to classic masks (transmission or reflection; binary, phase shift, hybrid, etc.), examples of other such patterned devices include:

-Programmable mirror array. More information about these mirror arrays is given in US Patent Nos. 5,296,891 and 5,523,193, which are incorporated herein by reference.

-Programmable LCD array. An example of this configuration is given in US Patent No. 5,229,872, which is incorporated herein by reference.

Fig. 1 schematically depicts a lithography apparatus LA. The lithography apparatus LA includes: an illumination system (also referred to as an illuminator) IL, which is configured to adjust the radiation beam B (eg, UV radiation, DUV radiation, or EUV radiation); a support structure (eg, photomask table) T, which Constructed to support a patterned device (eg, photomask) MA and connected to a first positioner PM configured to accurately position the patterned device MA according to certain parameters; a substrate table (eg, wafer table) WT, It is constructed to hold a substrate (such as a resist-coated wafer) W and is connected to a second positioner PW configured to accurately position the substrate according to certain parameters; and a projection system (such as a refractive projection lens system) ) PS, which is configured to project the pattern imparted to the radiation beam B by the patterned device MA onto the target portion C of the substrate W (eg, including one or more dies).

In operation, the illuminator IL receives the radiation beam from the radiation source SO, for example via the beam delivery system BD. The lighting system IL may include various types of optical components for guiding, shaping, or controlling radiation, such as refraction, reflection, magnetic, electromagnetic, electrostatic, or other types of optics Components, or any combination thereof. The illuminator IL can be used to adjust the radiation beam B to have the desired spatial and angular intensity distribution in its cross section at the plane of the patterned device MA.

The term "projection system" PS as used herein should be interpreted broadly to cover various types of projection systems suitable for the exposure radiation used or for other factors such as the use of immersion liquids or the use of vacuum, including refraction, Reflective, catadioptric, synthetic, magnetic, electromagnetic and electrostatic optical systems, or any combination thereof. It can be considered that any use of the term "projection lens" herein is synonymous with the more general term "projection system" PS.

Lithography devices can be of the type in which at least a portion of the substrate can be covered by a liquid with a relatively high refractive index (such as water) in order to fill the space between the projection system and the substrate-it is also called infiltrating lithography. More information on infiltration techniques is given in US Patent No. 6,952,253 and PCT Publication No. WO99-49504, which are incorporated herein by reference.

The lithography apparatus LA may also be of a type having two (dual stage) or more than two substrate tables WT and, for example, two or more support structures T (not shown in the figure). In these "multi-stage" machines, additional tables/structures can be used in parallel, or one or more tables can be prepared, while one or more other tables can be used to design the patterned device MA The layout is exposed onto the substrate W.

In operation, the radiation beam B is incident on a patterned device (eg, reticle MA) held on a support structure (eg, reticle stage T), and is patterned by the patterned device MA. With the mask MA traversed, the radiation beam B passes through the projection system PS, and the projection system PS focuses the beam onto the target portion C of the substrate W. With the aid of the second positioner PW and the position sensor IF (such as interferometric devices, linear encoders, 2D encoders or capacitive sensors), the substrate table WT can be accurately moved, for example in order to position different target parts C to radiation In the path of beam B. Similarly, the first positioner PM and possibly another position sensor (which is not in FIG. 1 Explicitly depicted) can be used to accurately position the reticle MA relative to the path of the radiation beam B. The mask MA and the substrate W can be aligned using the mask alignment marks M1, M2 and the substrate alignment marks P1, P2. Although the substrate alignment marks as described occupy dedicated target portions, the substrate alignment marks may be located in the space between the target portions (these marks are called scribe-lane alignment marks).

As shown in FIG. 2, the lithography device LA may form part of a lithography manufacturing unit LC (sometimes called a lithography cell (lithocell) or (lithography) cluster). The lithography manufacturing unit LC often includes A device for performing a pre-exposure process and a post-exposure process on the substrate W. Conventionally, these devices include a spinner SC for depositing a resist layer, a developer DE for developing exposed resist, for example for adjusting the temperature of the substrate W (for example for adjusting the resist The solvent in the layer) the cooling plate CH and the baking plate BK. The substrate handler or robot RO picks up the substrate W from the input/output ports I/O1, I/O2, moves the substrate W between different process devices, and delivers the substrate W to the loading cassette LB of the lithography apparatus LA. The devices in the lithography manufacturing unit, which are often collectively referred to as coating and development systems, are usually under the control of the coating and development system control unit TCU. The coating and development system control unit TCU itself can be controlled by the supervisory control system SCS. The system SCS may also control the lithography apparatus LA via the lithography control unit LACU, for example.

In order to accurately and uniformly expose the substrate W exposed by the lithography device LA, the substrate needs to be inspected to measure the properties of the patterned structure, such as overlay error between subsequent layers, line thickness, critical dimension (CD), etc. For this purpose, an inspection tool (not shown in the figure) may be included in the lithography manufacturing unit LC. If an error is detected, the subsequent exposure of the substrate or other processing steps to be performed on the substrate W can be adjusted, for example, especially when other substrates W of the same batch or batch are still to be tested before exposure or processing .

The detection device, which can also be referred to as a weighing and measuring device, is used to determine the properties of the substrate W, and especially to determine how the properties of different substrates W change or relate to different layers of the same substrate W How the attributes of the link change from layer to layer. The inspection device may alternatively be constructed to identify defects on the substrate W, and may for example be part of the lithography manufacturing unit LC, or may be integrated into the lithography device LA, or may even be a stand-alone device. The detection device can measure the attributes on the latent image (image in the resist layer after exposure), or the attributes on the semi-latent image (image in the resist layer after the PEB baking step) , Or properties on the developed resist image (where the exposed or unexposed portions of the resist have been removed), or even properties on the etched image (after the pattern transfer step such as etching).

Generally, the patterning process in the lithography device LA is one of the most decisive steps in the process, which requires the high accuracy of the dimensioning and placement of the structure on the substrate W. To ensure this high accuracy, the three systems can be combined in a so-called "overall" control environment, as schematically depicted in Figure 3. One of these systems is the lithography device LA, which (actually) is connected to the metrology tool MT (second system) and to the computer system CL (third system). The key to this "overall" environment is to optimize the cooperation between these three systems to enhance the overall process window and provide strict control loops to ensure that the patterning performed by the lithography device LA remains within the process window. The range of process window customization process parameters (such as dose, focus, overlap), within the process parameter range, a specific manufacturing process obtains a defined result (such as a functional semiconductor device)-usually within the process parameter range lithography process or patterning The process parameters in the process are allowed to change.

The computer system CL can use (part of) the design layout to be patterned to predict which resolution enhancement technology to use and perform calculus lithography simulations and calculations to determine which mask layout and lithography device settings to achieve the maximum patterning process Overall system window (depicted by the double arrows in the first scale SC1 in FIG. 3). Generally, the resolution enhancement technique is configured to match the patterning possibilities of the lithography device LA. The computer system CL can also be used to detect where in the process window the lithography device LA is currently operating (eg using input from the metrology tool MT) to predict attributions to eg Whether the process can be flawed (depicted by the arrow pointing to "0" in the second scale SC2 in FIG. 3).

The metrology tool MT can provide input to the computer system CL for accurate simulation and prediction, and can provide feedback to the lithography device LA to identify possible drifts in the calibration state of the lithography device LA (in FIG. 3 by the third Multiple arrows in scale SC3 are depicted).

In the lithography process, it is necessary to frequently measure the generated structure, for example, for process control and verification. The tool used to make such measurements is commonly referred to as the metrology tool MT. Different types of metrology tools MT for making such measurements are known to me, including scanning electron microscopes or various forms of scatterometer metrology tools MT. A scatterometer is a multi-functional instrument that allows the measurement of the parameters of the lithography process by having a sensor in the pupil or in a plane conjugate to the pupil of the scatterometer attached to the objective lens (measurement is often referred to as light Pupil-based measurement), or by measuring the parameters of the lithography process by having a sensor in the image plane or a plane conjugated to the image plane, in this case measurement is usually referred to as image or field Based measurement. The entire text is incorporated herein by reference in patent applications US20100328655, US2011102753A1, US20120044470A, US20110249244, US20110026032, or EP1,628,164A to further describe such scatterometers and associated measurement techniques. The aforementioned scatterometer can use light from soft x-rays and visible light to the near IR wavelength range to measure the grating.

In the first embodiment, the scatterometer MT is an angular resolution scatterometer. In this scatterometer, the reconstruction method can be applied to the measured signal to reconstruct or calculate the properties of the grating. This reconstruction can be generated, for example, by simulating the interaction of the scattered radiation with the mathematical model of the target structure and comparing the simulation results with the measurement results. Adjust the parameters of the mathematical model until the simulated interaction produces a diffraction pattern similar to the diffraction pattern observed from the real target.

In the second embodiment, the scatterometer MT is a spectral scatterometer MT. In this spectrum In the scatterometer MT, the radiation emitted by the radiation source is directed to the target and the reflected or scattered radiation from the target is directed to the spectrometer detector, which measures the spectrum of the specularly reflected radiation (that is, based on the wavelength And the measurement of the intensity of the change). From this data, the structure or profile of the target generating the detected spectrum can be reconstructed, for example, by tightly coupled wave analysis and nonlinear regression or by comparison with a simulated spectral library.

In the third embodiment, the scatterometer MT is an elliptical measurement scatterometer. The elliptical measurement scatterometer allows the determination of the parameters of the lithography process by measuring the scattered radiation for each polarization state. This metrology device emits polarized light (such as linear, circular, or elliptical) by using, for example, an appropriate polarizing filter in the illumination section of the metrology device. Sources suitable for metrology devices can also provide polarized radiation. The entire text is incorporated by reference in U.S. Patent Applications 11/451,599, 11/708,678, 12/256,780, 12/486,449, 12/920,968, 12/922,587, 13/000,229, 13/033,135, 13/533,110 and Various embodiments of existing ellipse measurement scatterometers are described in 13/891,410.

Another implementation of the metrology tool is an impact-based stacking and weighing tool, which is a measurement technique that uses optical (visible light) radiation to determine stacking by detecting images of specially designed stacking targets. Targets such as box-in-box or strip-in-strip targets are used to perform typical targets for image-based stacked pair (IBO) measurement. The entire text is incorporated by reference in the US Patent Application US20130208279 herein to further describe IBO-based measurements.

In one embodiment of the scatterometer MT, the scatterometer MT is adapted to measure by measuring the reflection spectrum and/or detecting asymmetry in the configuration (the asymmetry is related to the range of the overlap) Measure the stack of two misaligned gratings or periodic structures. Two (usually overlapping) grating structures can be applied in two different layers (not necessarily continuous layers), and the two grating structures can be formed in At roughly the same location on the wafer. The scatterometer can have a symmetric detection configuration as described in, for example, the jointly owned patent application EP 1,628,164A, so that any asymmetry can be clearly distinguished. This provides a direct way to measure misalignment in the grating. The stack between the two layers containing the targeted periodic structure can be found in PCT Patent Application Publication No. WO 2011/012624 or US Patent Application No. US 20160161863, which is incorporated herein by reference in its entirety. Another example of measuring the error through the asymmetry of these periodic structures.

When manufacturing lithographic devices with enhanced three-dimensional features (such as X-dot memory or 3D NAND structures), an opaque layer is required to ensure proper device processing. Generally, this layer is opaque (especially configuration) to visible radiation, depending on the application or type of material used for the opaque layer, this layer is transparent to infrared radiation. However, the technical blueprint predicts that a layer that is hardly transmissive to optical radiation (in the visible or infrared spectrum) is needed, with a strong preference for layers made of optically non-transmissive materials (such as metal layers). Therefore, determining the attributes of interest in the patterning process can be performed by techniques that do not use visible or infrared radiation.

The present invention describes a method for measuring parameters of a patterning process using acoustic waves or radiation. The present invention also describes a weighing and measuring device including a source of sound waves. In one embodiment, the patterning process parameters are stacked pairs. In one embodiment, the method for measuring the parameters of the patterning process uses images of measurement and measurement targets obtained using acoustic-based tools. An example of such an acoustic imaging tool is a surface acoustic microscope (SAM), and CFQuate, A. Atalar, HK Wickramasinghe described the operation in the publication in IEEE Proceedings (Vol. 67, No. 8) in August 1979 Principle, the full text of the case is incorporated by reference.

Generally speaking, the sound wave penetrates the material, which depends on the acoustic properties of the material. This is also for the case where the material is not optically transmissive, such as in the case of manufacturing metal layers such as 3D NAND structures. Acoustic microscopes use this principle to obtain the structure of structures embedded in materials The image, in one example, is the image of a grating embedded in the semiconductor layer stack. The depth of the image measured by an acoustic microscope depends on the attenuation of sound waves at the excitation frequency. The dependence on frequency is not straightforward. In metals, the main attenuation source results in "thermoelastic heat flow", as explained by C.F.Quate et al. in the content cited above, and the overall attenuation increases with the square of the frequency. In insulators, the main source of attenuation is due to collisions and damping induced by phonon gas. In semiconductors, a combination of these two effects can be expected. Usually the attenuation seems to be proportional to the square of the sound wave frequency. However, for very high sound frequencies (eg a few GHz), the experimental results have shown that the attenuation is slower. For example, Li and Cahill are incorporated by reference in this article in Phys. Rev. B 94 , 104306.

Therefore, in order to obtain a deeper penetration depth for an acoustic wave used to obtain an image of an embedded object in an acoustic microscope (an object such as a stacked target), the frequency of the acoustic wave needs to be reduced and therefore the wavelength needs to be increased. The effect of this relationship of the physical properties of sound waves in the material indicates that deeper embedded objects such as metrology targets need to have an increased size accordingly. In other words, the resolution of the image taken with an acoustic microscope decreases with the distance the object is buried. In the semiconductor industry, metrology targets are usually printed under opaque materials of a few hundred nanometers to a few microns. Therefore, imaging with audio frequencies up to several GHz is possible, so that it is possible to obtain spatial resolution in the micron or even submicron range.

In order to calibrate this effect, it is necessary to calibrate the loss of reflected sound power by the depth of the material. Calibration is also called V(z) curve. It represents the voltage detected at the acoustic transducer that varies according to the defocus of the sound wave. The V(z) curve reveals important information about the surface and underlying structure of the sample. As described by C.F.Quate et al. in Reference 35 cited above, acoustic microscopes are usually operated with a small defocus as a signal.

A typical overlay target suitable for acoustic overlay measurement can be composed of two adjacent grating groups Success: grating 301A (embedded grating) as shown in FIG. 4A and grating 302A (top grating) as shown in FIG. 4A. The grating 302A has a size between 1 μm and 10 μm pitch, which has, for example, a 50% duty cycle. The grating 301A has a size between, for example, a pitch of 1 micrometer and 10 micrometers. Assume that there is a metal layer of 1 micron W between these gratings. Another example of an opaque layer is formed from a few microns of amorphous carbon.

The acoustic microscope has an acoustic source that delivers sound waves having a frequency in the GHz range, for example, the source has a frequency of 1 GHz corresponding to a wavelength of 0.7 microns, and it has a numerical aperture of 0.5. Under these conditions, one can assume that there is a resolution of about 1 micrometer on the surface of the substrate that needs to be imaged by an acoustic microscope. The attenuation for the GHz system of W is about 2dB/cm. The attenuation for the GHz system for Ti is 10 dB/cm, and the attenuation for the GHz system for gold is 100 dB/cm. Assuming a value of 50dB/cm, the round-trip attenuation of the metal film is still 5x10 ^-4 dB/micron. Therefore, in the GHz range, attenuation is not a significant issue, and therefore the bottom grating may have a pitch in the range of 5 microns to 10 microns as calculated above. Attenuation becomes a larger problem at higher frequencies because it is inversely proportional to the square of the frequency, but for GHz systems, a power law of less than 2 can be expected. The image obtained using the measurement and configuration of FIG. 4A is shown in FIG. 4B, where 301B is the image of the bottom grating 301A and 302B is the image of the top grating 302A.

Hybrid metrology solutions include acoustic microscopes such as 301 of FIG. 4A, and optical microscopes such as 302 of FIG. 4A. The tool separation distance 310 is based on, for example, the size of the microscope, the target to be used, and the speed of the substrate support table Knowledge to be calibrated. In the example of FIG. 4A, the overlay is the relative distance measured between the edges 301AA and 302AA as measured from the images of the gratings 301A and 302A.

In one embodiment, the grating 301A and 4A of FIG. 4A are measured by an acoustic microscope. 302A both. The measurement means obtaining the image of each raster, obtaining the edges 301AA and 302AA, and determining the overlapping pair by the difference between the two edges 301AA and 302AA. An acoustic microscope measures the top grating 302A and the bottom grating 301A.

In an embodiment, the same configuration that operates as a "lens" for an acoustic microscope is modified to allow an optical configuration, such as an optical objective lens, as seen in FIG. 5. The same lens can be used to focus optical radiation 402 and acoustic radiation 401. By manufacturing a beam splitter on the acoustic lens, the same lens can be used as a light and acoustic lens. The material may be sapphire glass because it is transparent at optical wavelengths and is also used for acoustic lenses. By comparing the image obtained by using the optical component and the image obtained by using the acoustic component, the overlapping information is obtained. The entire text of which is incorporated herein by reference in European Patent Application 18153587.3 describes the operation of the device as shown in FIG. 5.

The acoustic microscope described in the above embodiments can be further improved by modifying it to allow phase detection or allowing the acoustic field to be better coupled into the target material. In one embodiment, the piezoelectric transducer scans the target emitting a pulsed acoustic field. Collect the transmitted and reflected echoes, which allows the image of the sample to be reconstructed in a coherent manner. In this embodiment, both amplitude and phase can be applied to signal processing. In another embodiment, a layer containing metamaterials can be used to modify the scanning acoustic microscope, which allows for improved coupling of the spatial variation of the acoustic field at or below the operating wavelength of the acoustic microscope.

Although specific reference may be made herein to the use of lithographic devices in IC manufacturing, it should be understood that the lithographic devices described herein may have other applications. Possible other applications include manufacturing integrated optical systems, guidance and detection patterns for magnetic domain memory, flat panel displays, liquid crystal displays (LCD), thin-film magnetic heads, etc.

Although it is possible to refer specifically to the content in the context of the lithography device in this document Embodiments of the invention, but embodiments of the invention can be used in other devices. Embodiments of the present invention may form part of a reticle inspection device, metrology device, or any device that measures or processes objects such as wafers (or other substrates) or reticles (or other patterned devices). These devices can often be referred to as lithography tools. This lithography tool can use vacuum conditions or ambient (non-vacuum) conditions.

Although the above may specifically refer to the use of embodiments of the present invention in the context of optical lithography, it should be understood that the present invention is not limited to optical lithography as long as the content background permits and can be used for other applications (such as imprinting Lithography).

Although specific embodiments of the invention have been described above, it should be understood that the invention can be practiced in other ways than those described. The above description is intended to be illustrative, not limiting. Therefore, it will be apparent to those skilled in the art that the described invention can be modified without departing from the scope of the patent application scope set forth below.

301‧‧‧ Acoustic Microscope

301A‧‧‧Bottom grating

301AA‧‧‧edge

301B‧‧‧Video

302‧‧‧Optical microscope

302A‧‧‧Top grating

302AA‧‧‧edge

302B‧‧‧Video

310‧‧‧Distance

Claims (3)

A weighing and measuring device includes: an acoustic source for generating sound waves; an optical source for generating light waves, wherein the weighing and measuring device uses the sound waves to obtain a first image of a first target and Use the light waves to obtain a second image of a second target, determine a characteristic of the first image and the second image, and determine a parameter of the patterning process as the characteristic of the first image and the first image The difference between the characteristics of the two images. A method for parameter determination, which includes using sound waves to measure a parameter of a patterning process, wherein sound waves are used to obtain a first image of a first target, and light waves are used to obtain a second image of a second target To determine a characteristic of the first image and the second image, and determine the parameter of the patterning process as a difference between the characteristic of the first image and the characteristic of the second image. The method of claim 2, wherein the characteristic is the edge of the image.

Images